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Materia medica, pharmacy, pharmacology and therapeutics online

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Examples: Unguentum Hydrargyri, Unguentum lodi.]

Vina. Wines are weak tinctures, [the drug being extracted
with white wine, containing twenty to twenty-five per cent, by
weight of absolute alcohol.]

Dose.

Vinum [Opii 3 20^; .20 i.aoc.c.

Colchici Radicis 5 15 ^ ; .30 i.ooc.c.

Antimonii 5 60 l ; .30 4.00 c.c.

Ipecacuanhse I ooTfl; .06 4.00 c.c.

Colchici Seminis 10 30 '"I; .60 2.00 c.c.

Ferri Citratis I 2 fig; 4.00 S.ooc.c.

Ergotse ")

- Ferri Amarum I l ~^ 3 ' 4.oo-i 5 .ooc.c.

Album as menstruum.

Rubrum "

Aromaticum as lotion. ]



36 PHARMACY.

With Vinum Antimonii and Vinum Ipecacuanhae the dose depends upoiv
the purpose for which the drug is used.

The following preparations [not occurring in the U. S. P.] are used :

Abstracta. [(Abstracts) solid, dry, powdered extracts of double the
strength of the crude drug. They are prepared by spontaneous evaporation
of an alcoholic tincture at a low temperature, mixing with it enough Sugar of
Milk to make the product weigh one-half of the original weight of the drug,
and then reducing it to a fine powder.]

Bougies. Solid cylinders impregnated with various drugs, and used for
introduction into the urethra, [ uterus,] or nose. They are made either of
gelatin (to be dipped in warm water before use) or cacao butter (to be dipped
in oil before use).

Cachets, made of wafer paper, consist of two watch-glass shaped halves,
enclosing the drug, which adhere when moistened. The cachet is swallowed,
and thus nauseous drugs are not tasted.

Capsules, [usually made of gelatin, are also used for enclosing medicines
so that they shall not be tasted, and they are now made for containing both
solid and liquid substances. They are either soft and elastic or hard. The
" empty capsule" is of the hard form and is made in two parts, the body to
be rilled when required for use, and the cap to fit tightly over it when filled].
Pills, cachets and capsules should be immediately followed by enough water to
wash them down.

Cataplasm ata [(Poultices). Soft, pasty masses used as a medium for
the external and local application of a moist heat, with or without the addition
of active medicaments. Any bland substance which will retain its heat and
moisture for a long time is applicable for this purpose, a little oil or glycerin
being often added to prevent caking. The substances chiefly used are flax-
seed, elm bark, bread and milk, bran, and oatmeal.

To make a poultice properly, the bowl in which it is mixed, the water, the
spatula for mixing and spreading the flannel or cheese-cloth on which it is
laid, must all be as hot as possible. The meal should be added gradually
to the boiling water, which is continually stirred. It should not be spread so
thick as to make it inconveniently heavy. ]

Cigarettes. The drug replaces the tobacco of an ordinary cigarette.

Clysters. [Another name for Enemata. ]

Collunaria. Fluids used as nasal douches. [This term is rarely used in
the United States.]

Collyria. Fluids used as eye washes.

Cremora. [Obsolete in the United States.] Creams are preparations
having glycerin, vaseline, or some substance as a basis, and used for external
application.

[Enemata (Enemas). Liquids intended for injection into the rectum and
designed to act medicinally, to evacuate the bowel mechanically, or to serve
as nutrients.] When their object is to empty the bowel, they are large in
bulk, to to 20 fl 3 [300 to 600 c.c.] ; when it is wished that they should be



PHARMACEUTICAL PREPARATIONS AND DOSES. 37

retained, they are small in bulk, 2 to 5 fl ^ [60 to 150 c.c. ], and after injec-
tion a towel may be pressed against the anus. Mucilage, made with starch,
is a good basis.

[Essentiae (Essences). Preparations of B. P. corresponding to Spirits,
U. S. P., but of 20 per cent, strength.]

Fomenta. Fomentations consist of flannels wrung out in hot water, to
which drugs may or may not have been added.

Gargarismata (Gargles) are fluid preparations for gargling.

Granules are small pills.

Guttae [(Drops). In England this term is used to designate liquid]
preparations to be dropped jnto the eye.

Haustus (Draught). This term is used when only a single dose of a fluid
preparation is required.

[Injectiones (Injections). These are of two kinds, Rectal (see Enemata),
and Hypodermatic. The latter are highly concentrated solutions intended for
use by means of a hypodermatic needle. (See p. 38.)

Inhalations. A common name for Vapors.]

Insufflationes. Powdered medicines or medicated powders designed for
blowing into the [nares], larynx or throat.

Lamellae (B. P.). Small, thin discs made with gelatin and glycerin, and
used to drop into the eye. They each weigh ^th of a grain [.0013 gm.].

Lanolinum is an ointment having hydrous wool fat as a basis.

Linctus. [(Never used in the United States.) A sweet mixture of a
thick, syrupy consistence.] It is to be swallowed slowly, being retained some
time in the mouth.

[Lotiones (Lotions). Liquid, usually aqueous preparations for external
use, commonly applied upon lint or muslin].

Mollinum. An ointment having for its basis mollin, a superfatted soap.
It is readily absorbed, and also readily washed off with water.

Nebulae [Sprays]. Solutions sprayed into the throat by means of an
atomizer.

[Oxymellita. Mellita containing acetic acid.]

Paste. A preparation to be applied as an ointment.

Pastillus (Pastils). [A name often applied to troches, and in England
limited to] those having glyco-gelatin as a basis.

Perles are small pills.

Pessus. Pessaries are solid preparations made like suppositories for in-
troduction into the vagina. [This term is rarely used in the United States.]

Pigmentum (A paint). A [liquid] preparation adapted for painting on
the skin, throat, etc.

Succi [(Juices). Expressed vegetable juices preserved by the addition
of a definite proportion of alcohol.]

Tabellae. (Tablets or Tabloids, [the latter of British usage].) Solid,
disc-like or lenticular bodies made by compression. ["Tablet triturates"
are composed of drugs which have been triturated before compression.] They



3 PHARMACOLOGY AND THERAPEUTICS.

are very popular, but are often useless, for they may be so hard and insoluble
that they are found in the faeces quite unaltered. [Tablets should always be
prescribed extemporaneously and freshly made.]

Vapores. [Liquid preparations intended for administration by inhalation
in form of vapor.]

Vaselinum. This term [in England] is applied to an ointment of which
the base is vaseline.

PHARMACOLOGY AND THERAPEUTICS.

Before describing the actions and uses of drugs we must con-
sider the manner, quantity and form in which to give them.

MODES OF ADMINISTRATION OF DRUGS.

(a) Into the blood-vessels by injection. This method is rarely used in
man, excepting for transfusion of physiological saline solution (a teaspoonful
of common salt to the pint of sterilized water at the temperature of the body)
in cases of great loss of blood.

(6) Into the subcutaneous tissues by hypodermatic injection. The skin
of the patient, where it is lax, should be raised between the thumb and fore-
finger of the operator's left hand ; the skin of the external surface of the fore-
arm is often selected. In his right hand he takes a perfectly clean syringe
containing the quantity of fluid to be injected, and fitted with an aseptic,
hollow, silver needle, which is thrust under the raised piece of skin, but not
into the muscles, for about an inch, care being taken to avoid wounding a
vein. The syringe is slowly emptied, then withdrawn, and the thumb pressed
lightly upon the seat of injection for a few seconds. The advantage of this
method is that the drug is surely and quickly absorbed. The fluid used must
not contain solid particles, nor be irritating, or abscesses will result ; it must
be aseptic, and therefore, if it is not freshly prepared, it may contain a little
carbolic acid or, better still, boric acid, for this is non-poisonous and non-
irritating. The bulk injected should, if possible, be about five minims; [.30
c.c.]. For injections that are not in constant use it is advisable to keep the
drugs in the form of [soluble tablets or] lamellae, and to dissolve one in a few
minims of water as required.

(f) Into serous cavities by injection. This method is rarely used in
man except when the object is antiseptically to wash out a serous cavity, as
the pleura which has been opened, or to produce adhesive inflammation, as in
the injection of irritants into the tunica vaginalis.

(</) Into mucous cavities. Drugs are most frequently given by the
mouth, to be absorbed from the mucous membrane of the stomach or intestines,
but the rate of absorption is much slower than from the subcutaneous tissue,
and will depend upon whether the drug is readily soluble in the gastro-intes-
tinal secretions, and whether it is given on an empty stomach, in which ca^e
it will be quickly absorbed ; or on a full one, when it will be slowly absorbed.



MODES OF ADMINISTRATION OF DRUGS. 39

[When it is intended that the drug shall act only in the intestine, pills, made
purposely insoluble in the gastric fluids, are administered.] Some drugs, given
by the mouth and absorbed from the stomach, probably never reach the general
circulation, as they are excreted in the bile by the liver. The drug must be in
a pleasant, palatable form, and generally so combined as not to irritate.

Drugs are sometimes given by the rectum in a solid form as supposi-
tories, in a liquid form as enemata or clysters ; but they are not dissolved
nor absorbed here so quickly as in the upper part of the gastro-intestinal
canal.

For local effects they may be given by the urethra or vagina (injections,
bougies, pessaries), or by the respiratory passages (inhalations, cigar-
ettes, sprays or nebulae for inhalations ; insufflations for blowing into
the throat and larynx ; pigmenta, gargarismata, trochisci, for a local effect
on the mouth and pharynx ; nasal douches for the nose). For sprays an
atomizer is required. Sometimes volatile drugs, as chloroform or amyl nitrite,
are inhaled for their general effect.

(e) By the skin. Some drugs may be absorbed from the skin if mixed
with some fatty substance, [especially hydrous wool fat.] In this way mer-
cury may be absorbed by being rubbed in ; but drugs are chiefly applied to
the skin as ointments, plasters, etc., for their local effect.

[Some drugs may be absorbed from the skin when they are volatilized. In
this way mercury is introduced into the system by fumigation.]

They are also applied to the eye and ear as drops and washes.



The study of doses is termed Posology. In determining the dose the
following considerations have to be borne in mind :

1. Age. The adult dose is that for a person between twenty and sixty
years old. [For women the dose should be somewhat smaller than for men.]

For children under twelve, add twelve to the age, and divide the age
by the number thus obtained. Thus, for a child aged eight the dose will be

8 2

= of an adult dose. From twelve to sixteen years from to i the
a -(- 12 5

adult dose is required, and from seventeen to twenty years from to |. There
are exceptions to this rule for individual drugs ; e.g., children take iron, cod
liver oil, arsenic, and chloral hydrate very well, but they can take only very
small doses of opium. [Cowling's rule divide age at next birthday by
twenty-four requires rather less calculation and is generally of sufficient
exactness.]

Above sixty years of age the dose should slightly diminish as age
increases.

2. Weight. In pharmacological experiments the dose should always be
expressed as a proportion of the weight of the animal. In man the weight is
not often considered, for it depends so much upon bone and fat, which are not
active tissues.



4O PHARMACOLOGY AND THERAPEUTICS.

3. Habit. A man who is constantly under the action of a drug becomes
very insusceptible to it. Thus an opium-eater requires enormous doses of
opium to produce any effect. A person who habitually takes purgatives re-
quires very strong ones to open the bowels.

4. Idiosyncrasy. The susceptibility to drugs varies very much. Some
persons are salivated by minute doses of mercury, others bear it very well, and
there is hardly a drug to which some people are not exceptionally indifferent
or susceptible.

5. Time of Administration. Drugs all act to greatest advantage when
given so that their effect will be produced at its natural time. Thus soporifics
act best when given in the evening, slowly acting purgatives when given over-
night, quickly acting ones when given before breakfast, ergot when given dur-
ing labor. [Drugs which are readily decomposed by the contents of the stom-
ach should be given when that viscus is empty, preferably a half hour before
the meal time. ]

6. Mode of Administration. We have seen that drugs are rapidly ab-
sorbed from the subcutaneous tissues. Therefore a smaller dose is required for
subcutaneous injection than when the same drug is given by the stomach, for
absorption is slow from the upper gastro-intestinal tract. It is slower still from
the rectum [therefore, to produce effects more immediately, the dose must be
larger]. Also certain drugs are excreted by the liver or destroyed in it when
given by the stomach. Absorption takes place quickly from an empty, slowly
from a full stomach.

7. Mental Emotion. Sometimes if the patient's mind is particularly
fixed on the action of the drug, a small dose is powerful. For example, often
if the patient is convinced he will sleep, a very small dose of morphine is all
that may be required.

8. Temperature. As the action of the drug on the organism is often
partly chemical, the temperature must, in cold-blooded animals and excised
structures, as muscle, etc., help to determine its action ; but the temperature of
man varies within so few degrees that this is not an important factor in medicine.

9. Preparation of Drug. A smaller dose of a soluble preparation, as a
tincture, will be required than of a solid preparation, as a pill, which will have
to be slowly dissolved before absorption [although in the latter case much de-
pends upon the process of manufacture].

10. Rate of Excretion. It is obvious that, other things being equal, for
prompt action a smaller dose will be required of a drug that is rapidly excreted
than of one which is slowly excreted. [It is also true that, in order to main-
tain a continuous effect from drugs which are rapidly excreted, the doses must
be repeated at shorter intervals.]

ii. Cumulative Action. Sometimes it is found that if a person has
been taking a drug regularly, but without the production of any poisonous
symptoms, these will suddenly develop. This is said to be due to the cumula-
tive action of the drug. It may be caused by the following circumstances :

(a) The drug may be absorbed more rapidly than it is excreted. This is



PRESCRIBING. 41

the cause of the cumulative action of mercury and lead, both of which are
excreted with difficulty by the kidney.

(l>) There may be a sudden arrest in the excretion of the drug. It is
probable that digitalis and strychnine, when the quantity of them in the tissues
reaches a certain amount, contract the renal vessels, and hence excretion is
arrested.

(c) It is possible that, owing to an alteration in the intestinal contents, a
drug which was previously very slowly dissolved becomes quickly dissolved,
and hence rapidly absorbed.

12. Disease. The physiological action of drugs, and consequently the
dose, are profoundly modified by disease. For example, a patient with peri-
tonitis will bear enormous doses of opium. Antipyretics, which do not affect
normal temperature, powerfully depress a febrile temperature.

[The tendency of modern therapeutics is towards smaller and more fre-
quently repeated doses. ]

PRESCRIBING.

The more complex prescriptions consist of

(1) The Basis, or principal active ingredient [curare\.

(2) The Adjuvans, or that which assists its action \_cito\.

(3) The Corrigens, or that which corrects its operation \_tuto~\.

(4) The Constituens, vehicle, or excipient, which imparts an agreeable
form [jucunde\.

Thus -the object of every prescription is to cure quickly, safely and pleas-
antly. For example [in Pilula Rhei Composita the rhubarb is the basis, the
aloes and myrrh form the adjuvans, and the oil of peppermint is the corrigens
to prevent the griping]. In Mistura Cretse the cinnamon water is the vehicle.
Many drugs do not require anything to assist their action or correct their op-
eration. [The scientific physician usually prefers to administer the remedies
separately, in order to more accurately observe their effect, and as well to dis-
continue, or change the dose of, any one which may be necessary.]

Incompatibility of ingredients should be particularly
avoided in prescriptions. There are three kinds of incompatibility:

(a) Chemical Incompatibility ; e.g., Glucosides should not be ordered
with free acids, which decompose them ; nor Alkaloids or Alkaloidal Salts
with alkalies, alkaline salts, tannic acid, iodides, or bromides, for they precipi-
tate them.

Examples of chemical incompatibility are the prescribing of (i) tannic acid
or substances containing it with alkaloids or metallic salts, especially those of
iron ; (2) vinegars or syrups containing acetic acid prescribed with carbonates
lead to the evolution of carbon dioxide ; (3) strychnine sulphate is decomposed
by potassium bromide, and strychnine is precipitated ; (4) chloral hydrate and
alkalies form chloroform ; (5) quinine sulphate and potassium acetate together
cause a voluminous precipitate of quinine acetate ; (6) lime water with mer-



42



PHARMACOLOGY AND THERAPEUTICS.



cury salts (this incompatibility is intentional in Lotio Nigra and Lotio Flava),
precipitates mercuric oxides; it decomposes carbonates and bicarbonates of
alkalies ; it precipitates solutions of quinine and morphine salts; (7) corrosive
mercuric chloride is incompatible with most substances.

The following table, drawn up by Potter \_Materia Medic a, Pharmacy and
Therapeutics, jth Ed., p. 540] shows the most important instance*
of solutions which mutually precipitate each other. The letter " /"'
means "forms a precipitate with"





a

JO


a

.


IH

O


g



1


umin




3




s *


*J




r^ *






3 jj.


3J


u .


sr .


<-2


SOLUTIONS OF


3%


C/) t,
C




"e5

8*


Sj2
wlS


o **>




M


a oa






I


O o




3~


s


p
1


_3


_3


_3

"o


Alkalies


p


p


p


P


P




Tannic acid


p


p


p






p


Carbonic acid and Carbonates . .


P


p


P


P


P




Sulphuric acid and Sulphates .






p


P






Phosphoric acid and Phosphates .


P


p


P


P


P


.


Boric acid and Borates ....


p


p


p








Hydrochloric acid and Chlorides .






p








Hydrobromic acid and Bromides






p








Hydriodic acid and Iodides . . .


p




p








Sulphides .




p


p








Arsenical Preparations ....




p


p








Albumin




p


p























With the following drugs it is particularly difficult to avoid chemical



incompatibility.
Antipyrin.
Chlorine in solution.
Liquid preparations of Iron.
Lead salts.
Zinc salts.
Silver salts.
Corrosive Mercuric Chloride

(especially).
Iodine and the Iodides.
All Bromides.



Potassium Permanganate.

Potassium Acetate.

Nitrites.

Tannic Acid.

Gallic Acid.

Acidum Hydrocyanicum Dilutum.

Mineral Acids.

Liquor Potassae.

Quinine Sulphate.

Tincture of Guaiacum.



Substances rich in oxygen, as chlorates, iodates, permanganates, picrates,
nitrates and bichromates should not be'mixed with readily oxidizable sub-



PRESCRIBING. 43

stances, such as charcoal, sulphur, iodine, carbolic acid, glycerin, turpentine,
and organic compounds generally, for explosive compounds are very liable to
be formed.

Poisonous compounds may be formed by the admixture of substances
in solution: e.g., potassium chlorate and the syrup of ferrous iodide liberate
iodine ; diluted hydrocyanic acid and calomel form mercuric cyanide ; potas-
sium chlorate and potassium iodide form, at the temperature of the body, a
poisonous compound, probably potassium iodate. Death has occurred owing
to patients having taken some of these careless prescriptions.

If, in a mixture, incompatibles are inevitable, they should both be diluted
with the vehicle before they are added to each other. The careful prescriber
will avoid combining any of the above incompatible substances.

(&) Physical Incompatibility. This occurs when the mixture of the sub-
stances will not form a clear solution ; e.g., insoluble powders and oils will not
mix with water, the addition of which, to some spirits and all resinous tinctures,
and to [fluid] extract of male fern causes a precipitate ; if an acid mixture is
flavored with liquorice, the acid precipitates glycyrrhizin ; an alcoholic solu-
tion added to chloral hydrate causes all the chloral to rise to the top.

In such cases the aqueous solution may be thickened so that the precipitate
is suspended in it to form an emulsion, but even then the mixture must be
shaken before a dose is taken. Mucilage of acacia, freshly made, is the
best emulsifying agent. The substances incompatible with it are mentioned
on p. 22. It should be made perfectly fresh. The addition of a little almond
oil improves its appearance.

I pt. of most fixed oils requires of acacia ^ pt., water I pt.
i pt. of balsam of Peru " 2 " i^

X pt. of oil of turpentine " I "I

Tragacanth [because its preparations keep better] is often used to form an
emulsion or a suspension, and sometimes yolk of egg or milk are employed.
Liquor Potassae much facilitates the admixture of fixed oils and water
[although] it often acts chemically on the ingredients of the prescription.
Tincture of senega aids the emulsification of any oil, even in small quantities,
itl x ; .60 c.c., being sufficient for an ounce ; 30. c.c., of a fixed oil. [Ex-
tractum quillajse, one grain; .06 gm., dissolved in one ounce; 30. c.c., of
water, will make a tolerably permanent emulsion with one ounce ; 30. c.c. of
fixed oil, or one drachm; 4. c.c., of oleoresin.] Magnesium carbonate is
employed to aid the diffusion of an oil in water through which air is to be in-
haled. Resinous tinctures require an emulsifying agent ; an equal part of
mucilage of acacia is the best. The suspension of oil of turpentine in mucilage
of acacia is a very common non-official example of an emulsion.

(t) Pharmacological Incompatibility ; e.g., the combination of purgatives
with astringents. Sometimes this is intentional, as in the occasional addition
of atropine to a hypodermatic solution of morphine. After the description of
each drug, those that are incompatible with it will be enumerated.



44 PHARMACOLOGY AND THERAPEUTICS.

THE PRESCRIPTION.

The details of a prescription should be written in the follow-
ing order :

Theyfrrf part is the Superscription, which is the sign R , an abbreviation
for Recipe, "Take."

The second part is the Inscription, consisting of the names of the drugs in
the genitive case (the vehicle in the accusative if ad is used with it), and their
doses in the accusative.

The third part is the Subscription, that is to say, the directions to the dis-
penser. This in England and most other countries is written in Latin, but in
France it is in the language of the country.

The/ourtA part is the Signature, that is to say, the directions to the patient
(from the Latin " Signelur," let it be labelled). This is written in English.

Theyf/?A part consists of the [physician's] name or initials at the bottom
on the right, the patient* s name at the bottom on the left, and under it the
date ; thus :

Superscription. R .

Inscription. Tincturae Ferri Chloridi, flj iij ; [12. c.c.], (basis).

Quininae Hydrochloratis, gr. xxx ; [2. gm. ], (adjuvans).
Magnesii Sulphatis, ^ij; [60. gm.], (corrigens).
Glycerini, fl ^ ij ; [60. c.c.], (corrigtns).
Infusum [Cinchonae], ad fl^ viij ; [240. c.c.], (excipient).
Subscription. Fiat mistura.

Signature. Take one table-spoonful three times daily, two hours after
meals. A. B. C. (physician's initials).

William Smith, Esq. (patient's name).

1 6th June, 1901 (date).

[On the continent and in countries where the metric system is generally
employed] the quantities, either of fluids or solids, are expressed in grammes,
so that the abbreviation is omitted ; [60. meaning 60. gm. or 60. c.c. as the
substance may be solid or liquid. ]



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